Add MTLS Aliases endpoints to the discovery endpoint

[RivinduM]

Proposed changes in this pull request

Add MTLS Aliases endpoints to the well known OIDC discovery endpoint.

When should this PR be merged

Need a framework version bump after wso2/carbon-identity-framework#5659 is merged.

Follow up actions

[List any possible follow-up actions here; for instance, testing data
migrations, software that we need to install on staging and production
environments.]

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[DMHP]

Do we need a configuration to enable /disable MTLS? For SaaS deployment can't ee depend on the existing config which we use to control other SaaS specific properties?

[RivinduM]

There's no backend config to identify a SaaS deployment. Hence added this config to enable MTLS aliases in the well known response

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PR builder started
Link: https://github.com/wso2/product-is/actions/runs/8890503743

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PR builder completed
Link: https://github.com/wso2/product-is/actions/runs/8890503743
Status: failure